spreiten

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spreiten (sing. spreite) From the German spreiten, meaning ‘to spread out’ or ‘to extend’, sedimentary laminae that result from the behaviour of an animal during feeding, excavation, or locomotion. They may be U-shaped, sinuous, blade-like, or spiralled, and they are always repeated over a small area. They reflect the intensive working of sediment for food. Well-defined spreiten are associated with Diplocraterion, Rhizocorallium, and Daedalus. In the latter they are arranged spirally around a single trunk. See FUGICHNIA.